is a game changer. >> reporter:theu.n. isinvestigating the incident. and congressional sources say that the intelligence committees have been briefed and that the administration has full authority to get militarily involved if chemical weapons, if there's any proof of chemical weapons. and in fact, that would be as the president has said, a game-changer. it would be the first u.s. military involvement in this conflict in the two-year conflict. natalie? >> andrea mitchell in jerusalem for us this morning, thank you, andrea. >>> u.s. officials tell nbc news this morning that new threats out of north korea are largely bluster. pyongyang says it will attack u.s. military bases in japan and guam, in response to joint u.s./south korean military exercises. >>> a internet attack on tuesday has been traced to a chinese internet address. but those addresses can be easily manipulated, meaning the exact source of the hack still remains uncertain. >>> a budget plan with sweeping cuts is on its way to the house for approval today. the spending bill would keep the government up and running throug